MotionGenesis: F=ma Software, textbooks, training, consulting.   Spin stability of 3D rigid bodies

MotionGenesis files to form/solve rotational equations of motion for a rigid body (aircraft).  
  Euler's method (angular momentum principle)     Program responses  
  Kane's method (generalized speeds)     Program responses  
MotionGenesis Spin stability
  • These files generate exact equations of motion in symbolic form.
  • Produce expressions for angular momentum which are constant in magnitude and direction during simulation.
  • Use the ODE command to create a simulation data file.   Or use .m, .c, or .f to generate fast, compact, easy-to-use MATLABŪ, C, or Fortran.
  • Note: Simulation data can be graphed with MATLABŪ, MotionGenesis plotting, etc. (in various graphics formats, e.g., .gif, ,jpg, .eps).
This problem helps explain why ``flat spin'' is dangerous
for aircraft (it is difficult to pull-out of this stable motion)
and why Explorer I (the first U.S. satellite) tumbled
(unstable rotational motion) in orbit around Earth.
YouTube and other videos
Spinning body   A   B   C   D   E
MotionGenesis Spin stability MotionGenesis Spin stability

Spin stability with orientation
Orientation via quaternions (Euler parameters):   Problem statement (.pdf)  
MotionGenesis dynamics (command file)     MotionGenesis program responses
Orientation via BodyXYZ angles
MotionGenesis dynamics (command file)     MotionGenesis program responses
MotionGenesis Weather Satellite (3D Rigid Body Spin Stability)